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List:       freedos-dev
Subject:    Internal vs External
From:       olivier_reubens () unicall ! be
Date:       1996-05-08 0:09:34
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I'm not sure if this has been said before but...

There is a clear reason why some commands are internal why others aren't.
On a machine with just one floppy disk, no harddrive. (quite common in the
early days of the PC), It was clear that in order to reduce the amount of
disk swapping and perform basic file manipulations that certain commands
(dir, copy, delete, rename, and lateron (dos 2.1+) directory management)
needed to be available at all time, having external commands would have
meant either execive amount of disk swaps or clutter up each single sided
160Kb (common disk format back then) disk with several Kilobytes of 'basic'
tools. 

Even now, when you're installing a new PC, all you have at hand is a boot
disk, and a non-functional PC with an unformatted, unpartitionned harddisk.
When you have several disks with things you want to install, it would be
very cumbersome to have all the basic commands external.

The command.com has been around for so long, and I've never heard anyone
complain that they couldn't and their own internal commands nor that they
couldn't remove some internal command.  Therefor, I would recommend to keep
the FreeDos command as closely doing what MSdos' command does, and not
overly spend time in making the command processor 'easily
extendable/modifiable/compile switch driven'  This may be a handy thing for
some people, and anyone smart enough is going to manage just that even if it
hasn't been specifically designed that way.
Olivier_Reubens@unicall.be


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